Privatize the first of the value maps.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@76634 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 300 insertions, 0 deletions

diff --git a/lib/VMCore/LLVMContextImpl.cpp b/lib/VMCore/LLVMContextImpl.cpp
index f34aba7..c72e3cb 100644
--- a/lib/VMCore/LLVMContextImpl.cpp
+++ b/lib/VMCore/LLVMContextImpl.cpp
@@ -19,6 +19,294 @@
 #include "llvm/MDNode.h"
 using namespace llvm;
 
+static char getValType(ConstantAggregateZero *CPZ) { return 0; }
+
+namespace llvm {
+template<typename T, typename Alloc>
+struct VISIBILITY_HIDDEN ConstantTraits< std::vector<T, Alloc> > {
+  static unsigned uses(const std::vector<T, Alloc>& v) {
+    return v.size();
+  }
+};
+
+template<class ConstantClass, class TypeClass, class ValType>
+struct VISIBILITY_HIDDEN ConstantCreator {
+  static ConstantClass *create(const TypeClass *Ty, const ValType &V) {
+    return new(ConstantTraits<ValType>::uses(V)) ConstantClass(Ty, V);
+  }
+};
+
+template<class ConstantClass, class TypeClass>
+struct VISIBILITY_HIDDEN ConvertConstantType {
+  static void convert(ConstantClass *OldC, const TypeClass *NewTy) {
+    llvm_unreachable("This type cannot be converted!");
+  }
+};
+
+// ConstantAggregateZero does not take extra "value" argument...
+template<class ValType>
+struct ConstantCreator<ConstantAggregateZero, Type, ValType> {
+  static ConstantAggregateZero *create(const Type *Ty, const ValType &V){
+    return new ConstantAggregateZero(Ty);
+  }
+};
+
+template<>
+struct ConvertConstantType<ConstantAggregateZero, Type> {
+  static void convert(ConstantAggregateZero *OldC, const Type *NewTy) {
+    // Make everyone now use a constant of the new type...
+    Constant *New = NewTy->getContext().getConstantAggregateZero(NewTy);
+    assert(New != OldC && "Didn't replace constant??");
+    OldC->uncheckedReplaceAllUsesWith(New);
+    OldC->destroyConstant();     // This constant is now dead, destroy it.
+  }
+};
+}
+  
+template<class ValType, class TypeClass, class ConstantClass,
+         bool HasLargeKey  /*true for arrays and structs*/ >
+class VISIBILITY_HIDDEN ContextValueMap : public AbstractTypeUser {
+public:
+  typedef std::pair<const Type*, ValType> MapKey;
+  typedef std::map<MapKey, Constant *> MapTy;
+  typedef std::map<Constant*, typename MapTy::iterator> InverseMapTy;
+  typedef std::map<const Type*, typename MapTy::iterator> AbstractTypeMapTy;
+private:
+  /// Map - This is the main map from the element descriptor to the Constants.
+  /// This is the primary way we avoid creating two of the same shape
+  /// constant.
+  MapTy Map;
+    
+  /// InverseMap - If "HasLargeKey" is true, this contains an inverse mapping
+  /// from the constants to their element in Map.  This is important for
+  /// removal of constants from the array, which would otherwise have to scan
+  /// through the map with very large keys.
+  InverseMapTy InverseMap;
+
+  /// AbstractTypeMap - Map for abstract type constants.
+  ///
+  AbstractTypeMapTy AbstractTypeMap;
+    
+  /// ValueMapLock - Mutex for this map.
+  sys::SmartMutex<true> ValueMapLock;
+
+public:
+  // NOTE: This function is not locked.  It is the caller's responsibility
+  // to enforce proper synchronization.
+  typename MapTy::iterator map_end() { return Map.end(); }
+    
+  /// InsertOrGetItem - Return an iterator for the specified element.
+  /// If the element exists in the map, the returned iterator points to the
+  /// entry and Exists=true.  If not, the iterator points to the newly
+  /// inserted entry and returns Exists=false.  Newly inserted entries have
+  /// I->second == 0, and should be filled in.
+  /// NOTE: This function is not locked.  It is the caller's responsibility
+  // to enforce proper synchronization.
+  typename MapTy::iterator InsertOrGetItem(std::pair<MapKey, Constant *>
+                                 &InsertVal,
+                                 bool &Exists) {
+    std::pair<typename MapTy::iterator, bool> IP = Map.insert(InsertVal);
+    Exists = !IP.second;
+    return IP.first;
+  }
+    
+private:
+  typename MapTy::iterator FindExistingElement(ConstantClass *CP) {
+    if (HasLargeKey) {
+      typename InverseMapTy::iterator IMI = InverseMap.find(CP);
+      assert(IMI != InverseMap.end() && IMI->second != Map.end() &&
+             IMI->second->second == CP &&
+             "InverseMap corrupt!");
+      return IMI->second;
+    }
+      
+    typename MapTy::iterator I =
+      Map.find(MapKey(static_cast<const TypeClass*>(CP->getRawType()),
+                      getValType(CP)));
+    if (I == Map.end() || I->second != CP) {
+      // FIXME: This should not use a linear scan.  If this gets to be a
+      // performance problem, someone should look at this.
+      for (I = Map.begin(); I != Map.end() && I->second != CP; ++I)
+        /* empty */;
+    }
+    return I;
+  }
+    
+  ConstantClass* Create(const TypeClass *Ty, const ValType &V,
+                        typename MapTy::iterator I) {
+    ConstantClass* Result =
+      ConstantCreator<ConstantClass,TypeClass,ValType>::create(Ty, V);
+
+    assert(Result->getType() == Ty && "Type specified is not correct!");
+    I = Map.insert(I, std::make_pair(MapKey(Ty, V), Result));
+
+    if (HasLargeKey)  // Remember the reverse mapping if needed.
+      InverseMap.insert(std::make_pair(Result, I));
+
+    // If the type of the constant is abstract, make sure that an entry
+    // exists for it in the AbstractTypeMap.
+    if (Ty->isAbstract()) {
+      typename AbstractTypeMapTy::iterator TI = 
+                                               AbstractTypeMap.find(Ty);
+
+      if (TI == AbstractTypeMap.end()) {
+        // Add ourselves to the ATU list of the type.
+        cast<DerivedType>(Ty)->addAbstractTypeUser(this);
+
+        AbstractTypeMap.insert(TI, std::make_pair(Ty, I));
+      }
+    }
+      
+    return Result;
+  }
+public:
+    
+  /// getOrCreate - Return the specified constant from the map, creating it if
+  /// necessary.
+  ConstantClass *getOrCreate(const TypeClass *Ty, const ValType &V) {
+    sys::SmartScopedLock<true> Lock(ValueMapLock);
+    MapKey Lookup(Ty, V);
+    ConstantClass* Result = 0;
+    
+    typename MapTy::iterator I = Map.find(Lookup);
+    // Is it in the map?  
+    if (I != Map.end())
+      Result = static_cast<ConstantClass *>(I->second);
+        
+    if (!Result) {
+      // If no preexisting value, create one now...
+      Result = Create(Ty, V, I);
+    }
+        
+    return Result;
+  }
+
+  void remove(ConstantClass *CP) {
+    sys::SmartScopedLock<true> Lock(ValueMapLock);
+    typename MapTy::iterator I = FindExistingElement(CP);
+    assert(I != Map.end() && "Constant not found in constant table!");
+    assert(I->second == CP && "Didn't find correct element?");
+
+    if (HasLargeKey)  // Remember the reverse mapping if needed.
+      InverseMap.erase(CP);
+      
+    // Now that we found the entry, make sure this isn't the entry that
+    // the AbstractTypeMap points to.
+    const TypeClass *Ty = static_cast<const TypeClass *>(I->first.first);
+    if (Ty->isAbstract()) {
+      assert(AbstractTypeMap.count(Ty) &&
+             "Abstract type not in AbstractTypeMap?");
+      typename MapTy::iterator &ATMEntryIt = AbstractTypeMap[Ty];
+      if (ATMEntryIt == I) {
+        // Yes, we are removing the representative entry for this type.
+        // See if there are any other entries of the same type.
+        typename MapTy::iterator TmpIt = ATMEntryIt;
+
+        // First check the entry before this one...
+        if (TmpIt != Map.begin()) {
+          --TmpIt;
+          if (TmpIt->first.first != Ty) // Not the same type, move back...
+            ++TmpIt;
+        }
+
+        // If we didn't find the same type, try to move forward...
+        if (TmpIt == ATMEntryIt) {
+          ++TmpIt;
+          if (TmpIt == Map.end() || TmpIt->first.first != Ty)
+            --TmpIt;   // No entry afterwards with the same type
+        }
+
+        // If there is another entry in the map of the same abstract type,
+        // update the AbstractTypeMap entry now.
+        if (TmpIt != ATMEntryIt) {
+          ATMEntryIt = TmpIt;
+        } else {
+          // Otherwise, we are removing the last instance of this type
+          // from the table.  Remove from the ATM, and from user list.
+          cast<DerivedType>(Ty)->removeAbstractTypeUser(this);
+          AbstractTypeMap.erase(Ty);
+        }
+      }
+    }
+
+    Map.erase(I);
+  }
+
+    
+  /// MoveConstantToNewSlot - If we are about to change C to be the element
+  /// specified by I, update our internal data structures to reflect this
+  /// fact.
+  /// NOTE: This function is not locked. It is the responsibility of the
+  /// caller to enforce proper synchronization if using this method.
+  void MoveConstantToNewSlot(ConstantClass *C, typename MapTy::iterator I) {
+    // First, remove the old location of the specified constant in the map.
+    typename MapTy::iterator OldI = FindExistingElement(C);
+    assert(OldI != Map.end() && "Constant not found in constant table!");
+    assert(OldI->second == C && "Didn't find correct element?");
+      
+    // If this constant is the representative element for its abstract type,
+    // update the AbstractTypeMap so that the representative element is I.
+    if (C->getType()->isAbstract()) {
+      typename AbstractTypeMapTy::iterator ATI =
+          AbstractTypeMap.find(C->getType());
+      assert(ATI != AbstractTypeMap.end() &&
+             "Abstract type not in AbstractTypeMap?");
+      if (ATI->second == OldI)
+        ATI->second = I;
+    }
+      
+    // Remove the old entry from the map.
+    Map.erase(OldI);
+    
+    // Update the inverse map so that we know that this constant is now
+    // located at descriptor I.
+    if (HasLargeKey) {
+      assert(I->second == C && "Bad inversemap entry!");
+      InverseMap[C] = I;
+    }
+  }
+    
+  void refineAbstractType(const DerivedType *OldTy, const Type *NewTy) {
+    sys::SmartScopedLock<true> Lock(ValueMapLock);
+    typename AbstractTypeMapTy::iterator I =
+      AbstractTypeMap.find(cast<Type>(OldTy));
+
+    assert(I != AbstractTypeMap.end() &&
+           "Abstract type not in AbstractTypeMap?");
+
+    // Convert a constant at a time until the last one is gone.  The last one
+    // leaving will remove() itself, causing the AbstractTypeMapEntry to be
+    // eliminated eventually.
+    do {
+      ConvertConstantType<ConstantClass,
+                          TypeClass>::convert(
+                              static_cast<ConstantClass *>(I->second->second),
+                                              cast<TypeClass>(NewTy));
+
+      I = AbstractTypeMap.find(cast<Type>(OldTy));
+    } while (I != AbstractTypeMap.end());
+  }
+
+  // If the type became concrete without being refined to any other existing
+  // type, we just remove ourselves from the ATU list.
+  void typeBecameConcrete(const DerivedType *AbsTy) {
+    AbsTy->removeAbstractTypeUser(this);
+  }
+
+  void dump() const {
+    DOUT << "Constant.cpp: ValueMap\n";
+  }
+};
+
+LLVMContextImpl::LLVMContextImpl(LLVMContext &C) :
+    Context(C), TheTrueVal(0), TheFalseVal(0) {
+  AggZeroConstants = new ContextValueMap<char, Type, ConstantAggregateZero>();
+}
+
+LLVMContextImpl::~LLVMContextImpl() {
+  delete AggZeroConstants;
+}
+
 // Get a ConstantInt from an APInt. Note that the value stored in the DenseMap 
 // as the key, is a DenseMapAPIntKeyInfo::KeyTy which has provided the
 // operator== and operator!= to ensure that the DenseMap doesn't attempt to
@@ -116,6 +404,14 @@ MDNode *LLVMContextImpl::getMDNode(Value*const* Vals, unsigned NumVals) {
   return N;
 }
 
+ConstantAggregateZero*
+LLVMContextImpl::getConstantAggregateZero(const Type *Ty) {
+  assert((isa<StructType>(Ty) || isa<ArrayType>(Ty) || isa<VectorType>(Ty)) &&
+         "Cannot create an aggregate zero of non-aggregate type!");
+
+  // Implicitly locked.
+  return AggZeroConstants->getOrCreate(Ty, 0);
+}
 
 // *** erase methods ***
 
@@ -128,3 +424,7 @@ void LLVMContextImpl::erase(MDNode *M) {
   sys::SmartScopedWriter<true> Writer(ConstantsLock);
   MDNodeSet.RemoveNode(M);
 }
+
+void LLVMContextImpl::erase(ConstantAggregateZero *Z) {
+  AggZeroConstants->remove(Z);
+}